US NAVAL AVIATION Special report Precision recovery A new GPS-based landing system will guide F-35 pilots to pin-point carrier touch-downs – and a portable version may also support rapid deployment of expeditionary air units GARRETT REIM LOS ANGElES be installed on the in-development Boeing MQ-25A Stingray unmanned in-flight refuel- he US Navy (USN) is preparing to ling tanker, while other USN aircraft will con- place an order for Raytheon’s Joint tinue to use the service’s existing tactical air Precision Approach and Landing navigation system. System (JPALS), to be installed on “In layman’s terms, it provides a kind of a Tall of its aircraft carriers and amphibious tunnel [on the head-up display] for the ­assault ships. ­airplane to fly through to get at the same land- The US Naval Air Systems Command ing point every time safely,” says Brooks ­(NAVAIR) on 25 March approved production Cleveland, Raytheon’s senior aviation adviser of the system, the aircraft component of for precision landing systems. which is installed on all three variants of the Raytheon promises that the system is 99% Lockheed Martin F-35 Lightning II, and reliable, guiding an aircraft to a 20x20cm should sign a contract with Raytheon at the (8x8in) spot on a carrier’s deck in almost all beginning of May. This will launch serial weather and up to Sea State 5: an ocean sur- ­production of the technology, says Raytheon, face condition where rough waves are crest- and lead to JPALS being installed on 11 nucle- ing as high as 2.5m (8ft). JPALS uses an en- ar-powered aircraft carriers and eight amphi­ crypted, anti-jam data link to connect to bious assault ships, with the first units to be software and receiver hardware built into delivered in 2020. F-35s and MQ-25A tankers, as well as an JPALS is a differential, GPS-based precision array of GPS sensors, mast-mounted antennas landing system that guides aircraft to land on and shipboard equipment. carrier or assault vessel decks. The navigation Pilots returning to a carrier for landing will equipment is used by the F-35 and will also first engage with JPALS at about 200nm (370km) away, where they start receiving range and bearing information. Then, at 60nm, the jet automatically logs into the JPALS queue, receiving more precise data while beginning two-way data-link communi- cation. At 10nm the pilot starts receiving pre- cision data for landing, following visual cues to land on an exact spot. Using JPALS is more covert than relying on a legacy tactical air navigation system and radio transmissions between a pilot and air traffic control, says CJ Jaynes, Raytheon exec- utive technical adviser for JPALS. “You do not have to have an air traffic control tower. You don’t have to have anyone talking to you,” she says. “A system can be on the ground and a pilot can go all the way to his landing point without any communication whatsoever.” Marine Corps S U Because the system relies on a direct en- JPALS equipment has been trialled extensively on land using US Marine Corps’ B-model crypted data link, the likelihood of interception 28 | Flight International | 30 April - 6 May 2019 flightglobal.com US NAVAL AVIATION Raytheon JPALS Technology will boost efficiency of embarked operations with AUTOMATED LANDiNG SYSTEMS US Navy‘s newest fighter AND THE US NAVY ARE OlD PALS JPALS, the Raytheon-developed Joint Precision Approach and Landing System being readied for installation on all the US Navy’s (USN’s) aircraft carriers and US Marine Corps ­amphibious assault ships, brings the latest GPS technology to bear on the oldest problem in naval aviation: landing safely on the moving runway that is the deck of a “flat top”. But the system, which should be de- livered from 2020, is not the first of its type – the navy has been using a prede- cessor system to address this problem since the 1980s. This current PALS “electronic landing aid” is radar-based, and has been ­installed on every USN carrier starting with the USS John F Kennedy, where it was certified for service in 1988 follow- ing trials. Developed by Textron Systems, PALS operates in one of three modes: fully automatic; pilot manual control based on cockpit displays of glide slope and centreline error; and pilot control based on approach ­controller talk-down. Two systems – one aircraft-based and one shipboard – operate indepen- dently, and must provide identical data to the incoming pilot. In a 2003 University of Tennessee master’s thesis assessing techniques for certifying that these independent elements are ­indeed providing identical information, John Ellis describes the system as “a vital component of modern naval ­aircraft recovery”. Ellis notes that in the John F Kennedy US Navy trials “the benefits the system provided to naval aviation were immediately rec- – a risk with a broadcast, which could give Grumman E-2 Hawkeye. The landing system ognised”. away the position of the aircraft or ship – is also can be added to any aircraft with a GPS, an PALS dates, ultimately, to the 1950s. lower, says Cleveland. inertial navigation system, a software repro- A Textron retirees newsletter article In July 2018, the USS Wasp amphibious grammable radio and enough computing notes that work by Bell – later a Textron ­assault ship used JPALS for the first time to power, says Jaynes. division – led to the first automatic land- guide a US Marine Corps (USMC) F-35B onto ing in 1954. The first automatic landing its deck. The USS Essex has also been using EXPEDITIONARY USE on a carrier deck was in 1957, with a the system. Both assault ships carry In January 2019, Raytheon demonstrated a navy pilot putting a Douglas F-3D down ­engineering, manufacturing and development portable version of JPALS guiding in a USMC on the USS Antietam. (EMD) units that will be replaced with short take-off and vertical landing F-35B to a Production systems were certified for ­production versions. touchdown at Yuma Proving Ground in use from 1963, but early examples Raytheon says Italy also plans to buy the ­Arizona. In attendance were personnel from ­apparently suffered from reliability system for one of its aircraft carriers, and the the USN, USMC and US Air Force (USAF), problems as they consisted of “more UK Royal Navy has expressed an interest in says the company. than 30 units of electronic equipment, buying two systems for its pair of Queen Eliz- Those services are interested in JPALS as a consisting of hundreds of vacuum tube abeth-class carriers. way to rapidly set up and facilitate air traffic operational amplifiers”. Raytheon thinks the system has potential control operations at expeditionary bases, Subsequent digitalisation – and now for other USN carrier-based aircraft too, in- which are part of a Pentagon idea to make the the advent of GPS – have been welcome cluding the Boeing F/A-18E/F Super Hornet, position of air forces unpredictable – a strate- improvements. ■ Bell ­Boeing V-22 Osprey and Northrop gy to keep near-peer adversaries such as ❯❯ flightglobal.com 30 April - 6 May 2019 | Flight International | 29 US NAVAL AVIATION Special report ❯❯ China or Russia on their heels should war goal we envision an end space where you break out. In particular, the USAF is showing “The ultimate goal we envision can handle up to 50 aircraft with that strong interest, says Jaynes. is handling up to 50 aircraft landing system,”­ says Jaynes. “And you could “The reason the air force is interested is touch down [at] points within 20nm of that they are developing a concept of operations with that landing system” ground station.” called ‘agile basing’, where they intend to CJ Jaynes For a second demonstration of the expedi- bring in their air wing, maybe stay in a loca- Executive technical adviser for JPALS, Raytheon tionary version of JPALS at NAS Patuxent tion for 24 to 48h, and then move the entire River in Maryland on 8 and 9 May, Raytheon air wing to a new location,” she says. packed in ruggedised cases or integrated into has invited back all of the US military servic- The USMC is also interested because it a Humvee or Polaris RZR light tactical all- es, plus international development partners could play a role in the Pacific theatre, says terrain vehicle, either of which could be on the Joint Strike Fighter programme. “Any Cleveland. “This system is perfect for that is- quickly air dropped. country that’s buying an F-35 – whether it’s an land hopping,” he says. “The goal is to have [a] multi-runway, A, B or C model – is a potential customer for The expeditionary version could be ­multi-aircraft [capability], with the ultimate this,” says Jaynes. ■ STRATEGY GREG WALRON singapore Modifications to launch F-35B from Japan’s Izumo-class warships are no surprise Some military secrets are better The US Marine Corps already It was just a case of when and navy. Beijing already has a single kept than others. The emer- operates the F-35B from its am- ­precisely how.” operational aircraft carrier, the gence of Tokyo’s real plan for its phibious assault ships, and the Fully loaded, the Izumo class 60,000t Liaoning, which operates pair of Izumo-class helicopter UK will fly the type from the ships displace 27,000t, which the Chengdu J-15; a Chinese destroyers was always, to naval Royal Navy’s (RN’s) pair of new compares with 22,000t for the copy of the Sukhoi Su-33.­ observers, more a matter of flat tops, HMS Queen Elizabeth RN’s former Invincible class.